Composite restorations or "white fillings" is composed of a resin matrix and filler materials, usually glass (silicon dioxide). Introduced in the 1960s, dental composites were confined to the front teeth because they were not strong enough to withstand the pressure and wear generated by the back teeth or posterior teeth. Since then, composites have significantly improved in strength and can be used successfully for the back teeth. Composites are not only used for restoring decay, but are also used for cosmetic improvements to the teeth by giving a natural color. Composites were initially intended for small cavities. However, technological improvements in material strength have made it possible to replace larger cavities with composite. Ideally too large of a cavity is best treated with another material such as a dental crown.

Advantages of composite include: A cosmetic breakthrough in dentistry. Whereas before dentists could only place silver or gold fillings in all cavity preparations, now patients have the option of a more pleasing and natural filling material. Composites are bonded to teeth which help support and insulate the remaining tooth structure. The bonding technique allows conservation of tooth structure. When placing composites, your dentist no longer relies on internal features of the tooth to hold a filling in place. Rather the composite filling is directly bonded to the tooth. Silver fillings rely on internal features of a tooth to hold it in place such as a supporting wall in a house.

Disadvantages of dental composites consist of: Staining of the material over time may occur from such agents as coffee or food stains. Patients may also experience slight sensitivity after initial placement. Composite fillings are usually more costly than silver fillings but are also a more time consuming procedure and technique sensitive. Also the life span of a composite is shorter than the older silver filling materials. This is because composites have less wear resistance than silver fillings.
Placement of the composite filling is usually accomplished in a one visit appointment. Your dentist first determines the color of your teeth. After the dentist removes the cavity (caries), a small amount of bonding agent in conjunction with an acidic solution is placed on the tooth. Your dentist will then place the composite in layers using a visible light source to cure or harden the material. Once cured, the composite is polished and contoured to a natural tooth shape.